//检查用户名是否注册
var isRegist = "";
$.ajax({
type: "POST",url: "registUsernameCheck.do",dataType : 'text',data : $('#form1').serialize(),async: false,success: function (data) {
if (data == 1) {
$("#usernametip").html("");
isRegist = "";
}
else {
$("#usernametip").html("<img src='<%=request.getcontextpath()%>/images/error.png'/><font color='red'>该用户名已经被注册！</font>");
isRegist = "registed";
}
}
});
if(isRegist.length == 0){
}else{
return false;
}
把异步处理设置 为false；即可给方法外部赋值：
<span style="color:#cc0000;"> async: false,</span>